Field of the Invention
The invention relates to a control device of a vehicle that includes an internal combustion engine as the motor, and more particularly relates to a control device for controlling an internal combustion engine that includes a supercharger and performs supercharging during a lean operation, in which an air-fuel ratio of an air-fuel mixture is set to a lean side of a theoretical air-fuel ratio.
Description of Related Art
Patent Literature 1 has disclosed an exhaust gas purification device of an internal combustion engine, which includes a lean NOx catalyst in the exhaust system. According to this device, when it is determined to be in a predetermined acceleration state where the torque required by the internal combustion engine is relatively large, control is performed to set the target air-fuel ratio to a relatively rich region (the air-fuel ratio is about 16 to 19) in the lean side region of the theoretical air-fuel ratio and perform exhaust gas recirculation. As a result, when acceleration is requested during the lean operation, the air-fuel ratio is set to the relatively rich region in the lean side region to meet the acceleration request and exhaust gas recirculation is performed, so as to increase the HC amount in the exhaust gas, maintain a favorable NOx purification rate with the lean NOx catalyst, and prevent an increase in the NOx emission amount due to change of the air-fuel ratio.